| The flaxseeds were pretreated by normal-pressure frying, microwave and high-pressure frying respectively, and pressed to produce oil. The effects of different pretreatment processes on smell, color, physicochemical indexes, nutritional component content, DPPH free radical scavenging capacity, fatty acid compositon and oxidative stability of pressed flaxseed oil were studied. The results showed that the physicochemical indexes such as color, acid value and peroxide value of pressed flaxseed oil pretreated by microwave, high-pressure frying and untreated were better than normal-pressure frying(170?℃, 45 min). In addition, pressed flaxseed oil pretreated by high-pressure frying had a pleasant flavor. The pressed flaxseed oils pretreated by high-pressure frying(1.0 MPa) and microwave (water content of flaxseed 17%, 700 W, 6 min) had good nutritional quality and strong DPPH free radical scavenging capacity. Different pretreatment processes had little effect on fatty acid composition of pressed flaxseed oil. The oxidative stability of pressed flaxseed oil pretreated by normal-pressure frying(170?℃, 45 min) was the best, followed by high-pressure frying(1.0 MPa).Therefore, it was feasible to use high-pressure frying technology to improve the quality of pressed flaxseed oil. |
